diff options
| author | Brian Kessler <brian.m.kessler@gmail.com> | 2017-08-17 23:26:31 -0700 |
|---|---|---|
| committer | Robert Griesemer <gri@golang.org> | 2017-08-18 12:48:10 +0000 |
| commit | 497f891fce8c6657ab28dfcd2e7195014f3a967f (patch) | |
| tree | f2492bf666bf3f583ca8bf8aa4ddf4d46bb7d51c /src/math/big/float.go | |
| parent | fe08ebaebb09cb0c45e3728a96d494f7f9f5c1b3 (diff) | |
| download | go-497f891fce8c6657ab28dfcd2e7195014f3a967f.tar.xz | |
math/big: recognize squaring for Floats
Updates #13745
Recognize z.Mul(x, x) as squaring for Floats and use
the internal z.sqr(x) method for nat on the mantissa.
Change-Id: I0f792157bad93a13cae1aecc4c10bd20c6397693
Reviewed-on: https://go-review.googlesource.com/56774
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Diffstat (limited to 'src/math/big/float.go')
| -rw-r--r-- | src/math/big/float.go | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/src/math/big/float.go b/src/math/big/float.go index afbed306f3..c042854eba 100644 --- a/src/math/big/float.go +++ b/src/math/big/float.go @@ -1311,8 +1311,11 @@ func (z *Float) umul(x, y *Float) { // TODO(gri) Optimize this for the common case. e := int64(x.exp) + int64(y.exp) - z.mant = z.mant.mul(x.mant, y.mant) - + if x == y { + z.mant = z.mant.sqr(x.mant) + } else { + z.mant = z.mant.mul(x.mant, y.mant) + } z.setExpAndRound(e-fnorm(z.mant), 0) } |